DictionaryEntry Structure


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Defines a dictionary key/value pair that can be set or retrieved.

Namespace:   System.Collections
Assembly:  mscorlib (in mscorlib.dll)

public struct DictionaryEntry

System_CAPS_pubmethodDictionaryEntry(Object, Object)

Initializes an instance of the DictionaryEntry type with the specified key and value.


Gets or sets the key in the key/value pair.


Gets or sets the value in the key/value pair.


Indicates whether this instance and a specified object are equal.(Inherited from ValueType.)


Returns the hash code for this instance.(Inherited from ValueType.)


Gets the Type of the current instance.(Inherited from Object.)


Returns the fully qualified type name of this instance.(Inherited from ValueType.)

The IDictionaryEnumerator.Entry method returns an instance of this type.

The foreach statement of the C# language (for each in Visual C++, For Each in Visual Basic) requires the type of each element in the collection. Since each element of the IDictionary is a key/value pair, the element type is not the type of the key or the type of the value. Instead, the element type is DictionaryEntry. For example:

foreach (DictionaryEntry de in openWith)
    Console.WriteLine("Key = {0}, Value = {1}", de.Key, de.Value);

The foreach statement is a wrapper around the enumerator, which only allows reading from, not writing to, the collection.

The following example demonstrates the use of DictionaryEntry to iterate through a Hashtable object.

// A simple example for the DictionaryEntry structure.
using System;
using System.Collections;

class Example
    public static void Main()
        // Create a new hash table.
        Hashtable openWith = new Hashtable();

        // Add some elements to the hash table. There are no 
        // duplicate keys, but some of the values are duplicates.
        openWith.Add("txt", "notepad.exe");
        openWith.Add("bmp", "paint.exe");
        openWith.Add("dib", "paint.exe");
        openWith.Add("rtf", "wordpad.exe");

        // When you use foreach to enumerate hash table elements,
        // the elements are retrieved as DictionaryEntry objects.
        foreach (DictionaryEntry de in openWith)
            Console.WriteLine("Key = {0}, Value = {1}", de.Key, de.Value);

/* This code example produces output similar to the following:

Key = rtf, Value = wordpad.exe
Key = txt, Value = notepad.exe
Key = dib, Value = paint.exe
Key = bmp, Value = paint.exe

Universal Windows Platform
Available since 8
.NET Framework
Available since 1.1
Portable Class Library
Supported in: portable .NET platforms
Available since 2.0
Windows Phone Silverlight
Available since 7.0
Windows Phone
Available since 8.1

Any public static ( Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

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